biological development summary

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Below is the article summary. For the full article, see biological development.

biological development, Gradual changes in size, shape, and function during an organism’s life that translate its genetic potentials (genotype) into functioning mature systems (phenotype). It includes growth but not repetitive chemical changes (metabolism) or changes over more than one lifetime (evolution). DNA directs the development of a fertilized egg so that cells become specialized structures that carry out specific functions. In humans, development progresses through the embryo and fetus stages before birth and continues during childhood. Other mammals follow a similar course. Amphibians and insects go through distinctive stages that are quite different. In plants, the basic pattern is determined by the arrangement of lateral buds around a central growing stem. Different rates of growth of the plant’s component elements then determine its shape and that of various parts. In both animals and plants, growth is greatly influenced by hormones; factors within individual cells probably also play a role.

puberty Summary

Puberty, in human physiology, the stage or period of life when a child transforms into an adult normally capable of procreation. A brief treatment of puberty follows. (See also adolescence.) Because of genetic, environmental, and other factors, the timing of puberty varies from person to person and

infancy Summary

Infancy, among humans, the period of life between birth and the acquisition of language approximately one to two years later. A brief treatment of infancy follows. For a full treatment of human mental development during infancy, see human behaviour: Development in infancy. The average newborn

psychological development Summary

Psychological development, the development of human beings’ cognitive, emotional, intellectual, and social capabilities and functioning over the course of a normal life span, from infancy through old age. It is the subject matter of the discipline known as developmental psychology. Child psychology

Three youths running down a street together.

adolescence Summary

Adolescence, transitional phase of growth and development between childhood and adulthood. The World Health Organization (WHO) defines an adolescent as any person between ages 10 and 19. This age range falls within WHO’s definition of young people, which refers to individuals between ages 10 and